Means for providing preferred service for bypassed signals for a bank of elevators



Dec. 27, 1955 R. A. BURGY MEA S O N F R PROV NG PREFERRED SERVICE FOR BYPASSED SIGNALS FOR A BANK OF ELEVATORS Filed April 8, 1953 IDI 2 Sheets-Sheet l 002 Z? 0000 0000 OOfiN 2 INVENTOR. RAYMOND ,4. 51/96) AT OR/VE R. A. BURGY Dec. 27, 1955 2,728,41 7 MEANS FOR PROVIDING PREFERRED SERVICE FOR BYPASSED SIGNALS FOR A BANK OF ELEVATORS Filed April 8, 1953 2 Sheets-Sheet 2 -ws20)w Y/PL) 300 -Z(PR)Z, 00,00

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INVENTOR. RAYMOND ,4. BU/PG Y I am BY United States Patent MEANS FOR PROVIDING PREFERRED SERVICE FOR BYPASSED SIGNALS FOR A BANK OF ELE- VATORS Raymond A. Burgy, Maumee, Ohio,

assignor to Haughton Elevator Company, Toledo, Ohio,

This invention relates to elevator control systems and in particular to means for improving service during rush hours.

During a normal business day the elevators in an office building are subjected to four heavy trafiic periods. The first of these occurs in the morning as the building occupants are arriving at the lobby floor and desire to be taken to their various floors. The second high demand occurs at noon when the occupants are leaving the building during their lunch hour. Then a short time later as they are returning to the building there is again a high demand for up service. The last heavy trafiic demand occurs later in the afternoon when the offices are closing and the people are leaving. During the up-peak traffic demands when the people are arriving at the building the service is well distributed because all of the waiting and loading occurs at the lobby floor, and the people are served in the order in which they arrive.

During the heavy down trafiic periods, however, it is usually impossible to provide such evenly distributed service. This occurs because a down traveling car leaving an upper terminal may become fully loaded at the first few floors and then bypass other calls while taking its load to the lobby floor. The next down traveling car may also become fully loaded at the upper floors and it also bypasses the calls on the intermediate or lower floors. As a result of this heavy trafiic from the upper floors it often happens that an intending passenger at an intermediate or lower floor may be forced to wait an unreasonably long time or in fact until the demand period is over before a down traveling car can stop for him. Various arrangements have been proposed to improve the service for the intermediate and lower floors during these down rush trafiic periods but in general these schemes for improving such service either interfere with or disrupt the schedulin of the elevators and thus do not solve the problem.

The principal object of this invention is to provide a control system for locating a floor at which the elevator first starts to bypass calls and to provide that the next down traveling car shall bypass all calls until it arrives at the highest down call previously bypassed.

Another object of the invention is to provide a motor driven switching arrangement that automatically locates the floor at which a car starts to bypass signals and in so locating the floor disconnects the stopping circuits for the floors above so that the next down car will travel directly to the bypassed call.

A still further object of the invention is to provide resetting means for restoring normal service as soon as a previously bypassed call has been answered.

More specific objects and advantages are apparent from the following description of a preferred embodiment of the invention.

According to the invention a motor driven selector switch is put in motion as an operator of a loaded car opens his bypass switch (to bypass signals) and closes the doors of his car. The motor driven selector switch moves to a position corresponding to the position of the elevator car. In so doing it disconnects the stopping circuits for any calls registered for floors above that elevator car. Consequently the next down traveling car receives no stopping signals until it arrives at the previously bypassed fioor. Whether or not there is a signal at that previously bypassed floor the second car will resume normal operations and stop for signals at that or any lower floor. As soon as the second car stops and answers that previously bypassed signal or passes that fioor with its bypass switch closed (normal operation) the selector switch is returned to its original position thus restoring service to all floors. In the event two or more cars are bypassing calls the selector switch moves to a position corresponding to the highest bypassed floor.

Suitable control circuits for this type of operation are illustrated in the accompanying drawings.

In the drawings:

Figure l is a diagrammatic representation of a bank of elevators equipped with floor selecting mechanisms.

Figure ll is a simplified front view of the carriage and contact support of a floor selecting or floor finding mechanism for a single elevator car.

Figure ill is a schematic wiring diagram illustrating the circuits employed in a control system constructed according to the invention.

These specific figures and the accompanying description are intended to merely illustrate the invention but not to impose limitations on its scope.

The improved control system for giving preferential service to those floor calls which have been bypassed by another car may be applied to banks of elevators having any number of cars. Figure I illustrates schematically an arrangement having four cars In to 1d respectively. Each of the cars 1 is supported by a cable 2 that is trained over a drive sheave 3 and connected to a counterweight 4. The drive sheave 3 is carried on an armature shaft 5 of a drive motor 6 that is mounted in a room at the top of the elevator shaft. Each elevator motor in addition to driving the car also drives a floor selecting iechanism 7 which comprises a bank of contacts cooperating with a moving carriage 8 arranged to complete control circuits according to the position of the car in the shaft. These contacts are part of the control mecha nism for the elevator.

Referring now to Figure II each of the floor selector mechanisms 7 comprises a panel board or combination of strips and a carriage 8 in a form of a bar that is carried on cables or chains 9 and 10 trained over a shaft 11 at the bottom of the board and a similar shaft at the top. The shaft 11 is driven by the elevator drive motor 6. The driving connection may include a differential mechanism or other compensating device in order that the carriage 8 may move over contacts 12, arranged in vertical rows on the board, in step with the movement of the car in the elevator shaft. A plurality of contact brushes 13 are mounted on the carriage 8 and arranged to contact the contacts 12 as the carriage moves upward or downward in step with the elevator car. The contacts 12 are arranged in vertical rows or lanes according to the various control functions required in the control of the elevator. Thus, there is one vertical lane of contacts for each control function and there are as many contacts in each vertical row as there are floors to be served by that elevator car.

Figure II shows four vertical lanes of contacts. It is to be understood, however, that the ordinary elevator control requires many more such lanes and also that the improved control for providing preferential service in a down direction may employ only three of these lanes.

Referring now to Figure III, the circuits employed to give the preferential service in connection with an elevator system serving at least seven floors are illustrated schematically. The equipment shown in Figure Ill includes six latch relays S21) to 87D inclusive corresponding to the second to seventh fioors. Similar latch relays are included for higher floors. Also included are a preference floor locator relay PL, a preference reset relay PR, and preference selector relays PSG) and 1 8(2). Also included is a motor operated selector switch. The selector switch, the floor relays $213 to 537D inclusive, the preference locator relay PL the preference reset relay PR are common to all cars regardless of the number of. cars in the banlr or in operation. The preference selector relays PS are individual to each car there being as many of these relays as there are cars in the bank.

In the key at the right in the figure the line or level of each of the leads is lettered, the lettering running from A at the top of the figure to IE5 at the bottom. Whenever operating coil appears in one of the horizontal lead lines of the diagram all of the contacts operated by that coil are listed in the key at the right according to the lines in which they appear. Thus, the preference locator relay PL which occurs in line Y has two sets of contacts one which is normally open and appears in line Y and a second set which is normally closed and which appears in line CC. To indicate that the latter set of contacts are normally closed the reference CC is underscored in the key at line level Y. Alternating current power for operating the control system is supplied through leads Li and L2. The contacts for the various relays are all shown in their normal position, i. e. the position they occupy when the relay coils are de-energized or in the case of the door relays when there is no signal registered and the relay is in its latched position.

When an intending passenger at one of the upper floors desires to call an elevator he pushes the corresponding hall button for his floor. The hall buttons H32 to HB7 corresponding to the various floors are arranged to energize the top coils of the corresponding floor relays 52D to 57D. Thus, if an intending passenger at the sixth floor pushes the H86 button current flows from line Ll through the top coil of relay 86D and through the button HB6 to the return line L2. This current flow unlatches the relay allowing its contacts to close thus preparing a stopping circuit from the lead Li through a selector switch sector 21, lead 22, and the now closed contacts 29 to a stopping contact 23, the latter being one of the contacts E2 on the floor selector control board. The selector switch sector 21 may be replaced by a series of cam operated switches without affecting the operation. When the next down traveling car arrives at the sixth floor its stop- 7 ping contact brush 2%, one of the brushes 13, following the lane of contacts including the contact 23 completes a circuit from the energized contact 23 through a stopping coil S( l shown in level G, for that particular elevator. This stopping circuit includes contacts D(l) of a down direction relay for elevator i and normally open contacts BPU) of a bypass relay for the first elevator car.

Each of the elevator cars is equipped with a bypass relay which in its de-energized condition permits the elevator c r to move past calls, in other words to bypass the calls. When the elevator is providing normal service the bypass relay, the operating coil of which is not shown, closes its normally open contacts so that in the example shown for floor six the circuit would be completed from the brush 24 directly through the directional relay contacts DH) and the bypass relay contacts 89(1) and the stopping circuit S to the return line L2. This energizes the stopping circuit for the car and it, in response, stops at that particular floor. The contacts 23 or the brush 2d cooperating with them is offset a suflicient distance to make the contact in time so that the stop may be safely made.

If the control is of a type employing an advancing signal the carriage 8, while it moves at the same relative speed as the car, leads the position of, the car by an amount proportional to the stopping distance of the car and stops suddenly when it reaches the contacts corresponding to a floor to be served. After the carriage 8 stops the elevator car then decelerates smoothly to come to a stop at that floor. In this case, the contacts 23 and cooperating brush are arranged directly in line with the other contacts corresponding to that particular floor.

As the elevator stops to answer the call registered by the relay 86D at the sixth floor it also completes a circuit from the lead L1 to L2 through the lower coil of the relay 86D, contact 25 of a reset lane of contacts of the floor selector 7, a brush 26 and contacts D1 and S1 in line P. When this circuit is completed the relay 86D is reset or returned to its latched position with the contacts 29 open. Should the elevator have gone past the sixth floor without serving or stopping at that floor the floor relay 36D would not have been reset when the brush 26 contacted the contact 25 because contact S1 in line F would not have been closed at that time.

While Figure 111 shows a second set of brushes 26b, 24b it is to be understood that these brushes are on a second floor selector machine corresponding to the second elevator and that the contacts 25 and 23 are duplicated on the second control.

Assuming now that the elevator has been loaded to capacity at the sixth floor, the operator throws the bypass switch in his car to de-energize the bypass relay and thus bypass calls at lower floors. When this occurs it is desirable that the next down traveling car, which may be at a higher floor, should bypass any intervening floors, proceed directly to the first call beneath the sixth floor. This is accomplished by interrupting the stopping circuits for any floors above and including the sixth floor. Since these stopping circuits are all energized through the sector 21 of a selector switch 27 all that is necessary is to rotate this selector switch 27 a suflicient distance to break the stopping circuits for the upper floors down to and including the sixth floor.

The selector switch 27 is driven by a motor 28. The operator on the first car, upon seeing that the car will be fully loaded at the sixth floor, throws the bypass switch for that car. Then, as the doors close, a circuit is completed at level AA from lead L1, through the coil of the preference selector relay PS(1), contacts CL(1) which are on the door closing relay of the first car, through contacts BP(1) of the bypass relay, to the return lead L2. As the door is closing the preference selector relay PS(1) is energized so that it closes its contacts in level DD to complete a circuit from line L1 to line L2 through contacts PL in line CC, motor winding 29 and a lead 30 at level DD. The motor 28 thereupon runs clockwise thus turning the sector 21, a contact arm 31, and an arm 32 that operates a switch 33 at level Y. The motor 28 continues to run until the selector arm 31 moves to the contact corresponding to the sixth floor at which time a circuit is completed from the switch 33, through the coil of the preference selector relay PL at level Y, through lead 34, arm 31, lead 35, contact 35 of the floor selector, brush 37 and now closed contacts PS(1) of the preference selector relay at level H, in lead 38 connected to the return lead L2. When the preference locator relay PL is energized through this circuit it closes its contacts PL at level Y, lead 40, to form a holding circuit. At the same time it opens its contacts PL in the motor energizing circuit at level CC so as to de-energize and stop the motor 28 thus leaving the selector switch with the arm 31 contacting the lead 35 leading to the sixth floor contacts and also with the sector 21 turned far enough to open the connection to the lead 22 thus insuring that the next following car will not stop at the sixth fioor even though a call is registered at that point. If it is desired to have the next car stop for those intending passengers who could not get in the first car, the ,sector 21 is not turned far enough to open the lead 22. Therefore if these intending passengers again push the hall button the next car will stop for them.

The setting of the selector switch 27 by the motor 28 is accomplished during the same interval of time that the elevator doors are closing. As soon as the doors are closed the CL(1) contacts in level AA open to de-energize the preference selector relay PS(1).

The selector switch 27 is reset to its original position when the next down traveling car, which is not bypassing signals, passes or stops at the floor at which the selector switch is set. Assuming now, for convenience, that the first car is the next down traveling car. As it reaches the sixth floor a circuit is completed from the line L1 to line L2 through the switch 33 at level Y, through a lead 38', the operating coil of a preference reset relay PR at level Z, a lead 39, lead 41 including bypass and directional relay contacts and extending up to the brush 37 and then through the contact 36, lead 35, selector switch arm 31 and lead 34 to the lead 40 connected to return line L2 through the now closed contacts PL at level Y. This energizes the preference reset relay PR so that it closes its contacts PR at level Z to complete a holding circuit at the same time that it closes its contacts at levels CC and DD. The latter contacts complete a circuit from line L1 through the contacts PR in line DD, 3. field 42 of the motor 28 and the contacts PR in line CC to operate the motor 28 in a counterclockwise direction thus driving the selector switch mechanism back toward its original or inactive position.

When the selector switch assembly 27 arrives at its original position the arm 32 opens the switch 33 thus deenergizing the preference floor locator relay PL and the preference reset relay PR. Thus the elevator control system is restored to normal operation and any down traveling car will answer all down calls. The inclusion of the down directional relay contacts D(1), D(2), etc. in the resetting circuits for the preference reset relay PR insures that an up traveling car will not reset the selector switch. If an up traveling car could reset the selector switch then that car would by traveling up to the top and starting down again restore the control and answer all calls and thus destroy preference circuits that are required to serve the previously bypassed calls.

This structure and circuit thus provides means for determining the floor at which a car starts to bypass calls, namely the selector switch assembly; means for resetting that selector switch after another car has answered the bypassed call, or has passed that floor while operating in its normal condition; and means for interrupting the stopping circuits for all floors above the bypassed floor thus insuring that the next down traveling car will ignore those calls and proceed directly to the bypassed floor.

While the diagram shows relays for seven floors it is easy to apply to any number of floors by merely adding additional positions on the selector switch and additional contacts on the floor selector machines. Likewise the number of elevators that may be controlled is unlimited. The equipment may be applied to any number of elevators since only the preference selector relays PS and the regular stopping circuits of each car have to be duplicated for each car. The stopping contacts energized from the floor relays S7D etc. are provided on each floor selecting machine so there is no distinction as to which car may start to bypass or which following car will answer the bypassed calls.

Various modifications of the circuit and structure may be made without losing the advantages obtained by causing a following down traveling car to bypass floors and begin answering down calls at a previously bypassed floor.

Having described the invention, I claim:

1. In a signal control system for a bank of elevators, in combination, floor call registering means common to all the elevators, a floor selector machine for each elevator, a reversible motor, a cam operated by the motor,

a plurality of contacts that are closed sequentially by the cam, 21 series of contacts that are opened progressively by the cam, said series of contacts being arranged in series between a source of power and stopping circuit contacts of the floor call registering means, a relay that is energized when an elevator is conditioned to by-pass a signal, contacts on the relay for running the motor in a first direction, a second relay, means including the plurality of cam operated switches and contacts of the floor selector machines for energizing the second relay when the motor driven cam reaches a position corresponding to the position of the elevator that is conditioned to bypass signals, contacts controlled by the second relay for stopping the motor, a third relay having contacts for operating the motor in reverse, and means actuated when an elevator reaches the floor corresponding to the cam position for energizing the third relay.

2. In a signal control system for a bank of elevators, in combination, floor call registering means common to all the elevators of the bank, a floor selector machine for each elevator, a signal by-pass circuit for each elevator, a cam, a plurality of contacts that are successively closed by the cam, a series of contacts that are progressively opened by the cam, said series of contacts being connected in series between a source of power and selector machine stopping circuit contacts corresponding to the first floor to be approached, the selector machine contacts for floors ahead of said first floor being connected to intermediate points of said series circuit, and means for driving the cam to a position corresponding to the first floor bypassed by an elevator to open the stopping circuits for floors behind the by-passed floor, said means comprising a motor, a first relay that is energized when an elevator by-passes a signal for driving the motor to advance the cam, a second relay that is energized when the cam reaches a position corresponding to the by-passed floor for stopping the motor, and a third relay that is energized when another elevator stops at the by-passed floor for driving the motor to return the cam to its home position.

3. In a signal control system for a bank of elevators, in combination, floor call registering means common to all the elevators of the bank, a floor selecting machine for each elevator, means on each elevator for by-passing stop signals, a lane of stop contacts on each floor selecting machine cooperating with the stopping circuits for the elevators, a set of contacts in the call registering means for each floor connected to all the selector machine stop contacts for that floor, cam operated switches for at least some of the floors, a power supply circuit from each set of call registering means contacts to a source of power with each circuit including in series the cam-operated switches corresponding to all floors behind the floor the contacts of which are to be supplied, a cam for opening the switches in order starting with the switch corresponding to the first floor to be reached, a second series of cam operated switches, a motor for driving the cam, and means controlled jointly by the second series of cam operated contacts and contacts of the floor selecting machines for stopping the motor when the cam reaches a position corresponding to a by-passed signal.

4. In a signal control for a bank of elevators, in combination; a system of floor call registering means and floor selector machines for establishing a stopping circuit as an elevator answers a floor call; means on each elevator for by-passing floor calls; a cam; means responsive to elevator position, cam position, and said by-pass means for driving the cam to a position corresponding to a bypassed signal; switches actuated by the cam adapted to interrupt the stopping circuits for all floors behind a by-passed floor, and means actuated by the stopping of an elevator at a by-passed floor for driving the cam to its home position.

5. In a signal control for a bank of elevators, in combination, a floor selecting machine for each elevator, a

floor call registering means, means on each elevator for Dy-passing floor calls, means for establishing stopping circuits for each elevator, said means comprising a stopping contact on each floor selecting machine for each floor, a contact in the call registering means for each floor, and a plurality of cam actuated switches, said switches being connected in series between a source of power and the call contact for the first floor to be approached with intermediate contacts being connected to intermediate switches of the series, a cam for opening said switches in order, a motor for driving the cam, a first relay for each elevator that is energized by the by-pass means, said relay having contacts to complete a forward driving circuit for the motor, cooperating contacts on the floor selecting machine and cam operated switches, a second relay, said second relay being energized through said cooperating contacts and having contacts arranged to stop the motor when the cam position corresponds to the by-passed floor, a third relay arranged to drive the motor in reverse, and a circuit for energizing the third relay that includes said cooperating contacts and switches and contacts of a by-pass means that are closed when the elevator is answering calls, whereby said cam is positioned according to by-passed calls to interrupt the stopping circuits for floor calls behind the lay-passed call until such call is answered.

References Cited in the file of this patent UNITED STATES PATENTS 2,619,197 Glaser et a1 Nov. 25, 1952 

